Key reference: Hohmann, C.D., et al., Effects of high phenolic olive oil on cardiovascular risk factors: A systematic review and meta-analysis. Phytomedicine, 2015. 22(6): p. 631-40.
One-sentence summary: High phenolic olive oils lead to a small reduction in systolic but not diastolic blood pressure and oxidized LDL compared to low phenolic olive oils, and there was no difference in cholesterol, triglycerides and malondialdehyde.
Study type: Systematic literature and meta-analysis of 8 RCTs.
Diet: Diets containing high phenolic olive oil (>150 mg/kg) vs. low phenolic olive oil (5 mg/kg).
The studies included both healthy subjects and subjects with heart disease or its risk factors. All studies were from Europe (5 from Spain, 2 from the Netherlands and 1 from Italy).
High phenolic olive oil vs. low phenolic olive oil resulted in:
Quality assessment: The Cochrane risk of bias tool was used to assess all studies. One study had a low risk of bias whilst all other studies had an unclear risk of bias.
The bottom line: Some evidence for the positive effects of high phenolic olive oil on reducing systolic blood pressure, but the available data are too limited to draw a solid conclusion. Future research should specifically focus on the efficacy of high phenolic olive oil in blood pressure reduction, including dose-response trials.
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